Active clinical trials for "Insulin Resistance"

The aim of the current study is to investigate the ability of antioxidants found in cocoa ('flavanols') to increase the body's sensitivity to the hormone insulin. 32 overweight or mildly obese women, who are otherwise healthy, will be recruited. Subjects will attend the laboratory on 3 occasions after fasting from midnight. The 1st visit is a medical screening, with laboratory visits 2 and 3 separated by 4 weeks, during which time subjects will consume a cocoa drink (containing either high or low amounts of flavanols) twice a day. Subjects will record their food intake for 3-days before visit 2 and in week 3 of consuming the cocoa. They will also eat a diet of standard macronutrient composition for 3 days before visits 2 and 3. During the 5 hour laboratory visits, subjects will have a scan to assess their body composition using a low-dose x-ray machine (Dual Energy X-ray Absorptiometry; DEXA), and have their insulin sensitivity measured using a 3 hour hyperinsulinemic, euglycaemic Clamp.

This study will evaluate the potential beneficial cardiometabolic effect of moderate (5%) weight loss and progressive (5%, 10%, and 15%) weight loss in obese adults without diabetes. Participants will be randomly assigned to one of 2 groups. Group 1: supervised weight loss group (low-calorie diet). Group 2: supervised weight maintenance group (normal diet). Of those assigned to group 1, half of the participants will lose 5% of their body weight and the other half will lose 5%, 10%, and 15% of their weight over time under the guidance of a dietitian. Research testing will be repeated at each time point (5%, 10%, and 15% weight loss). In group 2, research testing will be repeated after six months.

Insulin resistance has important implications in the pathogenesis of the polycystic ovary syndrome (PCOS) and insulin-sensitizing drugs are considered a useful therapeutic approach. Reduction of insulin levels with administration of insulin sensitizing agents has been found to be beneficial in lowering both hyperinsulinemia, hyperandrogenemia, and restoring ovulation. Metformin alone or in combination with oral contraceptives (OCs) has been widely used in the long term treatment of women with PCOS in whom it modifies the ovarian morphology, improves intraovarian androgen levels, and enhances systemic and local insulin resistance. Despite to these beneficial effects, several side effects have been reported due to the long term administration of this drug. In the recent years, inositol has found more and more space in the reproductive clinical practice. Indeed, inositol have been classified as "insulin sensitizing agent" and it is mainly used as a chronic treatment for PCOS. Inositol exists in 9 different isomers and in particular several studies on Myo-inositol and D-chiro-inositol were reported. In this study myo-inositol versus D-chiro-inositol treatments were compared to placebo in women with PCOS and with or without insulin resistance.

Alterations in fatty acid mobilization and oxidation may be primary adaptations responsible for the improvements in metabolic health after a single session of endurance exercise. The investigators will determine the effect of a single session of endurance exercise on whole-body fatty acid mobilization and oxidation, IMTG concentration and the expression of factors that regulate these processes in skeletal muscle of 11 women with abdominal obesity (age: 18-45y). In addition, the investigators will evaluate how these factors, and exercise, effect insulin signalling and insulin sensitivity. Every effort will be made to recruit subjects from ethnic and minority groups. Before participating in the study, subjects will be informed of all the procedures and potential risks, and they will sign an informed consent form approved by The University of Michigan Institutional Review Board. Eligible volunteers will participate in three separate trials, in a randomized order. In two trials subjects will eat exactly the same amount of calories, except in one trial they will exercise (eucaloric + exercise) and in the other trial they will remain sedentary (hypercaloric). In a third trial subjects will again remain sedentary but instead they will ingest appropriate calories to maintain caloric balance (eucaloric + sedentary). By doing this the investigators are also able to investigate the effect of acute caloric perturbations on insulin sensitivity, because it is possible that the enhanced insulin sensitivity evident after exercise, as compared to the sedentary state, is due to caloric deficit and not the exercise bout, per se.

Many of the beneficial metabolic effects of endurance exercise training are not due to adaptations to weeks, months, or even years of training, but rather much is due to the response to the most recent exercise session(s). Therefore, the investigators contend that lifestyle interventions for obese individuals should be tailored to optimize the metabolic effects of the most recent exercise session(s). But the "dose" of exercise necessary to evoke these beneficial responses is not known, and the mechanisms responsible for these improvements are poorly understood. The findings from these studies will: 1) establish the minimum "dose" of a single exercise session necessary to improve insulin sensitivity the next day in obese adults, 2) characterize the underlying metabolic factors responsible for the improvement in insulin sensitivity, and 3) assess the cumulative metabolic adaptations that occur over days, weeks, and months of a low-intensity/low-volume lifestyle exercise program. Findings from these studies will provide valuable information for the development of lifestyle programs aimed at maximizing the key metabolic health benefits of each exercise session in obese patients.

The purpose of the study is to investigate some of the mechanisms behind severe insulin resistance and to determine the dose response to insulin in patients with type 2 diabetes mellitus.

The combination of impaired insulin sensitivity and insulin secretion is thought to be the basis of type 2 diabetes. Increased free fatty acids levels impair insulin action in muscle and liver, but also systemic inflammation processes play a role in the development of insulin resistance. This study compares the effects of fat and inflammation on insulin sensitivity, systemic inflammation, energy metabolism, vascular system and neural function in healthy humans.

The aim of the study is to isolate the direct effects of endotoxin on glucose, lipid and protein metabolism. Eight healthy volunteers are enrolled. The hypothesis is that endotoxin will induce insulin resistance, lypolysis and proteolysis acutely.

An increase of plasma free fatty acids impairs insulin secretion and insulin sensitivity, thereby playing an important role in causing type 2 diabetes. Lipotoxicity plays an important role in the progression from normal glucose tolerance to fasting hyperglycemia and coversion to frank type 2 diabetes. A recent publication in the journal Science showed that buphenyl, when given to obese diabetic mice, resulted in normalization of hyperglycemia, restoration of systemic insulin sensitivity, resolution of fatty liver disease and inhancement of insulin action in liver, muscle and adipose tissue. the mechanism of action is believed to be due to reduction of endoplasmic reticulum (ER) stress. Buphenyl is currently approved for the treatment of rare inherited disorders of the urea cycle. We plan to administer Buphenyl orally to humans at a dose far lower than that used for the treatment of urea cycle disorders for 2 weeks prior to the testing of pancreatic function. One potential mechanism whereby chromically elevated plasma FFAs and glucose impairment beta cell function and insuln sensitivity is by ER stress and this can be prevented by administeration of buphenyl.

This study will test the effects of resistant starch type 4 on blood sugar and hunger in adults with Type 2 diabetes.